Question

Step 4 of the pentose phosphate pathway converts ribulose-5- phosphate to ribose-5-phosphate. Which glycolytic reaction does this reaction resemble and what type of enzyme catalyzes it?

Short answer

Reaction 2 of the glycolysis process explains the conversion of glucose-6-phosphate to fructose-6-phosphate occurs in the presence of phosphoglucoisomerase.

Step-by-step solution

Glycolysis

Glycolysis is the initial process of breaking down glucose to release energy for cellular metabolism. An energy-consuming phase and an energy-releasing phase make up glycolysis.

Step 2 of the glycolytic reaction resembles the given reaction of the pentose phosphate pathway

Ribulose-5-phosphate is converted into ribose-5-phosphate by ribulose-5-phosphate isomerase in step 4 of the pentose phosphate pathway. Because an isomerase mediates the conversion of an aldose to a ketose, this reaction parallels the glycolysis step-2 process.

In the presence of phospho-glucose isomerase, glycolysis reaction 2 explains the transition of glucose-6-phosphate (G6P) to fructose-6-phosphate in the conversion of an aldose to ketose.

Hence, the given reaction resembles step 2 of the glycolytic pathway.